Brake-valve for air-brakes



(No Model.) 2 Sheets-Sheet 1. H. R. MASON.

BRAKE VALVE FOR AIR BRAKES. 1 No. 450,332. 7 Patented Apr. 14,1891.

TNE nonms PETERS m, micro-mum, msnmawn, u. c.

(No Model.) 2 Sheets Sheet 2. H. R. MASON. BRAKE VALVE FOR AIR BRAKES. No. 450,332. Patented Apr. 14,1891.

m m l/ w a w m W 6 g M a. 5W

j 3 B W UNITED STATES HARRY R.'MASON, OF CHICAGO, ILLINOIS.

BRAKE-VALVE FOR 'AIR-BRAKES.

SPECIFICATION forming part of Letters Application filed July 31, 1890- To all whom it may concern:

Be it known thatI, HARRY R. MASON, a citiaen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented a new and useful Improvement in Brake-Valves for Air-Brakes, of which the following is a specification.

My invention relates to an improvement in a certain valve device employed in connection with air-brakes for railway-cars, particularly of the class in general use, wherein the brakes are applied automatically by reducing. the pressure of air in the train-pipe and released by increasing the air-pressure therein.

The mechanism for generating and controlling the air-pressure in the class of air-brakes above defined comprises, generally stated, an air-pump, a main reservoir connected with the pump and in which the pressure is stored, all located upon the locomotive, anda trainpipe extending from the main reservoir to auxiliary reservoirs and brake-cylinders on each carof the train, suitable shut-off cocks and couplings being provided along the trainpipe between cars. An operating-valve, called the engineers brake-valve, is interposed in the train-pipe upon the locomotive, by means of which the flow of air to the train-pipe from the main reservoir for releasing the brakes and the escape of air from the train-pipe for applying the brakes is regulated, and it is to improvement in this engineers brake-valve that my invention particularly relates.

As hitherto constructed, the brake-valve in question is defective, for the reason that, while the brakes are held released under pressure from the main reservoir, the accidental parting of a coupling between the cars or sudden breakage of or undue leakage in the trainpipe or attendant parts from any unforeseen cause applies the brakes by permitting the rapid escape of air from the main reservoir and train-pipe, which, if not checked in time by the engineer, quickly exhausts the pressure in the main reservoir and requires the renewal of the pressure-supply by means of the pumps before the brakes can be again released. This necessarily occasions delay before the train can be again started, and has in the past been the cause of serious accidents.

Patent No. 450,332, dated April 14, 1891.

Serial No. 360,534. (No model.)

My object is to overcome the objection above set forth to the engineers brake-valves as hitherto constructed by providing such a valve device which will operate automatically to check the flow of air from the main reservoir to the train-pipe when the pressure in the latter is suddenly reduced through any undue cause.

In the drawings, Figure 1 is a view in the nature of a diagram, showing my improvement in elevation as applied to an air-brake system; and Fig. 2, an enlarged section taken on the line 2 of Fig. l and viewed in the direction of the arrow.

A denotes the main reservoir for compressed air, which is connected with a suitable airpump, (not shown;) A, a pipe leading from the main reservoir to the engineers brakevalve device B; C, the train'pipe leading from the valve B; C, a branch of the train-pipe in which triple-valve mechanism C (of the wellknown construction) is interposed and which communicates with an auxiliary reservoir D and brake-cylinder E.

The shell of the brake-valve device B is for convenience formed in two parts 13 B which are bolted together, as shown, and constitute each a valve in itself, as hereinafter described. In the part B, which is the engineers brake-valve proper, are the port If, at which the pipe A is connected, ports t and 15 which lead, respectively, into an indirect or supplemental passage (1 and direct passage h, and port 15 leading to the outerair, all of the said ports being in the relative positions shown. The rotary valve-plug s is provided with the diagonal passage 3 and branch passage s and the passage 8 is widened .at the month by flaring in the horizontal plane to an extent which permits the plug to be turned to move the opposite end of the passage 8 from one of the ports 25' or t to the other without shutting off its communication with the port t. In the part B is an outlet 7, to which the passages h and (1 lead and which open into the train-pipe C. The passage q in the part B is provided with an auxiliary valve 19, held normally open by a spring 0. The valve 19, as shown, is in the form of a piston provided at its periphery with a small passage 19' and mounted upon a rod 19 which extends from opposite sides thereof and moves at one end in a guide-socketn in the shell and at the leased by turning the plug 5 to bring the passage s coincident with the port 1?, which causes the air to flow from the main reservoir through a direct channel h r to the train-pipe. \Vhen the brakes are released and an equilibri um of the air-pressu re isestablished throughout the system, the plug is turned to bring its passage 5 coincident with the port If, as shown in the drawings, which directs the pressure from the main reservoir through the indirect channel q r to the train-pipe and thus maintains the equilibrium. The size of the passage 7 and resilient'quality of the spring 0 are such that the passage of air from the main reservoir to overcome any reduction of pressure due to slight leakage in the system will not effect closure of the valve 19. In the event of a sudden exhausting of the pressure in the train-pipe, however, the force of the rush of air from the main reservoir will press the valve 1) against the resistance of the spring to its seat, and thus close the passage 12' to prevent any further escape of air from the main reservoir. \Vhen the damage to the system which occasioned the sudden exhaust has been repaired, the plug may be turned again to bring'the passage 3 coincident with the port t and the pressure for releasing the brakes again established without material loss of time. When it is desired to reduce the air-pressure in the system to apply the brakes, the plug is turned to bring the branch passage 8 coincident with the port 23 which closes the ports 25 and t and brings the passage s coincident with the port t. A passage is thus opened from the brake-pipe to the outer air. Upon the shell of the brakevalve should be indicated, in any suitable manner, the distances to which the handle is to be turned to move the plug to any of the positions described, and a spring Z may be provided upon the handle to engage notches in the shell to hold the handle in any one of the positions desired.

While the valves above specifically described are the ones I prefer to employ, they are subject to modifications in the matter of details of construction and exact relative location, and I do not for that reason confine my invention to the particular construction set forth.

by Letters Patent, is

valve device, of a main air-passage and supplemental air-passage between the main reservoir and train-pipe, an engineers valve between the main reservoir and train-pipe, operative at will to direct the aii pressure through either the main passage or supplemental passage, and an auxiliary valve in the supplemental passage, operating by abnormal reduction of back-pressure in the train-pipe to shut off communication between the latter and the main reservoir through the supplemental passage, the said auxiliary valve forming the sole obstruction in the said supplemental passage, whereby it is exposed to baclcpressure from the train-pipe, substantially as and for the purpose set forth.

2. The combination, in an engineers brakevalve device, of a main air-passage and a supplemental air-passage, both leading to the train-pipe, a passage A, leading from the main reservoir, an engineers valve operative at will to direct the air-pressure from the passage A to either the said main or supplemental passage, and an auxiliary valve in the supplemental passage, operating by abnormal reduction of baclopressure in the train-pipe to shutoff communication between the latter and the main reservoir through the supplemental passage, the said auxiliary valve forming the sole obstruction in the said supplemental passage, whereby it is permanently exposed to back-pressure from the train-pipe, substantially as and for the purpose set forth.

3. An engineers brake-valve device having the inlet 6 from the main reservoir A, outletpassage h, and supplemental outlet-passage q, which communicate with the train-pipe C, an engineefis valve in the valve device, operating to direct the air-pressure from the inlett to either of said outlet-passages and when leading to the passage (1 to close the passage 7t, and an auxiliary valve in the passage q, forming the sole obstruction in that passage and operating by abnormal reduction of backpressure in the train-pipe to shut off communication between the latter and the main airreservoir through the passage q, substantially as described. I

a. An engineers brake-valve device having the inlet 25 from the main reservoir A, outletpassage h, supplemental outletpassage q, both of which lead to the train-pipe C, and an exhaust-opening 6 an engineers valve in the valve device, affording at will communication between the inlet t and either passage h or q or between the passage 71. and exhaustopening i and an auxiliary valve in the passage q, forming the sole obstruction in that passage and operating by abnormal reduction of back-pressure in the train-pipe to shut off communicution between the latter and the main reservoir through the passage (1, substantially as described.

5. In an engineers brake-valve device, the combination of the engineers valve B, provided with the inlet i from the main reser- 1. The combination, in an engineers brakevoir A, outlet-passages h g, leading to the train-pipe, exhaust-opening t and plug 5, having the diagonal passage 5 and branch passage 8 and a valve device B through the passage (1 abnormal reduction of back- 10 which the passage (1 extends, having avalvepressure in the train-pipe will cause the valve seat q and a piston-valve p in the said pas- 1) to be closed and shut off the escape of air sage, the valve being mounted upon a stem p from the main reservoir through the passage and having asmall opening 19' through it near q, substantially as described.

its edge, a spring 0, operating normally to HARRY R. MASON. maintain the valve p away from its seat, and guides at n for the opposite ends of the stem 13 whereby when the passage 3 is coincident with In presence of J. W. DYRENFORTH, M. J. FROST. 

